tag:blogger.com,1999:blog-8693614218792476252.post77575507725066931..comments2015-07-22T08:13:45.207-07:00Comments on Looking For Detachment: Where on (Google) Earth #170Silver Foxhttp://www.blogger.com/profile/03131032620978696727noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-8693614218792476252.post-68151145813497597602009-08-12T15:45:03.079-07:002009-08-12T15:45:03.079-07:00Folks, WoGE#171 is ready for inspection. Have fun!...Folks, <a href="http://pluffi.smugmug.com/gallery/4206594_PBb4L#618178825_drw2V" rel="nofollow">WoGE#171</a> is ready for inspection. Have fun!Peter Lhttp://pluffi.smugmug.com/gallery/4206594_PBb4Lnoreply@blogger.comtag:blogger.com,1999:blog-8693614218792476252.post-5451524278933299452009-08-11T13:10:07.872-07:002009-08-11T13:10:07.872-07:00I forgot about the benitoite - there are some grea...I forgot about the benitoite - there are some great little rock shops in New Idria - or at least *were* in 1982!Silver Foxhttp://www.blogger.com/profile/03131032620978696727noreply@blogger.comtag:blogger.com,1999:blog-8693614218792476252.post-10219627420508703552009-08-11T12:53:37.875-07:002009-08-11T12:53:37.875-07:00Yes, Silver Fox, you&#39;re right, I&#39;ve overlo...Yes, Silver Fox, you&#39;re right, I&#39;ve overlooked the New Idria mercury mining. And I also have entirely forgotten that here is the locus tipicus for benitoite (BaTiSi3O9, a cyclosilicate formed in hydrothermally altered serpentinites), named after the near-by San Benito River. It&#39;s the official state gem of California and, more importantly to me, owing to its intense blue cathodoluminescence, it is the &quot;spot finder&quot; sample used in the adjustment of beam size and shape of electron microprobes :-)<br /><br />Anyway, I&#39;ll post #171 asap.Peter Lhttp://pluffi.smugmug.com/gallery/4206594_PBb4Lnoreply@blogger.comtag:blogger.com,1999:blog-8693614218792476252.post-41440909521659340482009-08-11T12:17:52.809-07:002009-08-11T12:17:52.809-07:00That&#39;s a great description, Peter, of the New ...That&#39;s a great description, Peter, of the New Idria antiform. I&#39;d only mention that New Idria is in the north part of the view, more-or-less the center of the historic mercury mining in the district.<br /><br />So - it&#39;s up to you again - for WoGE #171! :)Silver Foxhttp://www.blogger.com/profile/03131032620978696727noreply@blogger.comtag:blogger.com,1999:blog-8693614218792476252.post-17575477206861839312009-08-11T11:51:12.330-07:002009-08-11T11:51:12.330-07:00View centered at 36.372N, 120.669W; this is the Ne...View centered at 36.372N, 120.669W; this is the New Idria serpentinite diapir which forms the core of the Coalinga antiform in the southern Diablo Range, California. It is flanked by folded Mesozoic and Lower Tertiary marine sedimentary units (visible in the southern and northern thirds of the view). All these units together form an asymmetric actively rising anticline. Northwards, the serpentinite diapir thrusts along high-angle faults over Late Cretaceous shales and sandstones of the Upper Great Valley Sequence and metagreywackes of the Jurassic and Cretaceous Franciscan Complex; in the southern part it is in thrust contact chiefly with the Franciscan Complex. The far northeastern corner of the view is dominated by mostly Eocene marine sediments. The New Idria serpentinite has been buoyantly detached from its mantle source region (still undecided whether it represents underplated Farallon abyssal peridotites, the mantle section of the Coast Range Ophiolite, or the mantle wedge itself) and, upon diapiric ascension, it has entrained a series of low- and high-grade crustal blocks (greenschists, blueschists, jadeitites, garnet amphibolites, and eclogites).Peter Lhttp://pluffi.smugmug.com/gallery/4206594_PBb4Lnoreply@blogger.comtag:blogger.com,1999:blog-8693614218792476252.post-14807316572323831902009-08-10T18:53:23.011-07:002009-08-10T18:53:23.011-07:00No idea where, but looks like there&#39;s a trappe...No idea where, but looks like there&#39;s a trapped valley in between those angular mountains.Gaelynhttp://www.blogger.com/profile/05784162697113288888noreply@blogger.com